package com.mjgy.utils;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.io.UnsupportedEncodingException;
import java.net.URL;
import java.net.URLConnection;
import java.net.URLDecoder;
import java.net.URLEncoder;
import java.util.List;
import java.util.Map;

import javax.servlet.http.HttpServletRequest;

/**
* @ClassName
* @Description
* @author 
* @date 2018年8月20日 下午2:24:03
*/
public class HttpRequest {

	private final static String ENCODE = "UTF-8"; // 编码
	
	/**
     * 向指定URL发送GET方法的请求
     * 
     * @param url
     *            发送请求的URL
     * @param param
     *            请求参数,请求参数应该是 name1=value1&name2=value2 的形式。
     * @return URL 所代表远程资源的响应结果
     */
    public static String sendGet(String url, String param) {
        String result = "";
        BufferedReader in = null;
        try {
            String urlNameString = url + "?" + param;
            System.out.println(urlNameString);
            URL realUrl = new URL(urlNameString);
            // 打开和URL之间的连接
            URLConnection connection = realUrl.openConnection();
            // 设置通用的请求属性
            connection.setRequestProperty("accept", "*/*");
            connection.setRequestProperty("connection", "Keep-Alive");
            connection.setRequestProperty("user-agent",
                    "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1;SV1)");
            // 建立实际的连接
            connection.connect();
            // 获取所有响应头字段
            Map<String, List<String>> map = connection.getHeaderFields();
            // 遍历所有的响应头字段
            for (String key : map.keySet()) {
                System.out.println(key + "--->" + map.get(key));
            }
            // 定义 BufferedReader输入流来读取URL的响应
            in = new BufferedReader(new InputStreamReader(
                    connection.getInputStream()));
            String line;
            while ((line = in.readLine()) != null) {
                result += line;
            }
        } catch (Exception e) {
            System.out.println("发送GET请求出现异常！" + e);
            e.printStackTrace();
        }
        // 使用finally块来关闭输入流
        finally {
            try {
                if (in != null) {
                    in.close();
                }
            } catch (Exception e2) {
                e2.printStackTrace();
            }
        }
        return result;
    }
 
    /**
     * 向指定 URL 发送POST方法的请求
     * 
     * @param url
     *            发送请求的 URL
     * @param param
     *            请求参数,请求参数应该是 name1=value1&name2=value2 的形式。
     * @return 所代表远程资源的响应结果
     */
    public static String sendPost(String url, String param) {
        PrintWriter out = null;
        BufferedReader in = null;
        String result = "";
        try {
            URL realUrl = new URL(url);
            // 打开和URL之间的连接
            URLConnection conn = realUrl.openConnection();
            // 设置通用的请求属性
            conn.setRequestProperty("accept", "*/*");
            conn.setRequestProperty("connection", "Keep-Alive");
            conn.setRequestProperty("user-agent",
                    "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1;SV1)");
            // 发送POST请求必须设置如下两行
            conn.setDoOutput(true);
            conn.setDoInput(true);
            // 获取URLConnection对象对应的输出流
            out = new PrintWriter(conn.getOutputStream());
            // 发送请求参数
            out.print(param);
            // flush输出流的缓冲
            out.flush();
            // 定义BufferedReader输入流来读取URL的响应
            in = new BufferedReader(
                    new InputStreamReader(conn.getInputStream()));
            String line;
            while ((line = in.readLine()) != null) {
                result += line;
            }
        } catch (Exception e) {
            System.out.println("发送 POST 请求出现异常！"+e);
            e.printStackTrace();
        }
        //使用finally块来关闭输出流、输入流
        finally{
            try{
                if(out!=null){
                    out.close();
                }
                if(in!=null){
                    in.close();
                }
            }
            catch(IOException ex){
                ex.printStackTrace();
            }
        }
        return result;
    } 
    
    /**
     * 获取真实的IP地址
     * 
     * @param request
     * @return
     */
    public static String getAddressIp(HttpServletRequest request) {
		String ip = "";
		
		// X-Forwarded-For:Squid 服务处理
		String ipAddresses = request.getHeader("X-Forwarded-For");
		
		if (ipAddresses == null || ipAddresses.length() == 0 || "unknown".equalsIgnoreCase(ipAddresses)) {
	        //Proxy-Client-IP：apache 服务代理
	        ipAddresses = request.getHeader("Proxy-Client-IP");
	    }

	    if (ipAddresses == null || ipAddresses.length() == 0 || "unknown".equalsIgnoreCase(ipAddresses)) {
	        //WL-Proxy-Client-IP：weblogic 服务代理
	        ipAddresses = request.getHeader("WL-Proxy-Client-IP");
	    }

	    if (ipAddresses == null || ipAddresses.length() == 0 || "unknown".equalsIgnoreCase(ipAddresses)) {
	        //HTTP_CLIENT_IP：有些代理服务器
	        ipAddresses = request.getHeader("HTTP_CLIENT_IP");
	    }

	    if (ipAddresses == null || ipAddresses.length() == 0 || "unknown".equalsIgnoreCase(ipAddresses)) {
	        //X-Real-IP：nginx服务代理
	        ipAddresses = request.getHeader("X-Real-IP");
	    }

	    //有些网络通过多层代理，那么获取到的ip就会有多个，一般都是通过逗号（,）分割开来，并且第一个ip为客户端的真实IP
	    if (ipAddresses != null && ipAddresses.length() != 0) {
	        ip = ipAddresses.split(",")[0];
	    }

	    //还是不能获取到，最后再通过request.getRemoteAddr();获取
	    if (ip == null || ip.length() == 0 || "unknown".equalsIgnoreCase(ipAddresses)) {
	        ip = request.getRemoteAddr();
	    }
	    return ip;
	}
    
    /**
     * URL 解码
     * 
     * @param url
     * @return
     */
    public static String getURLDecoderString(String url) {
    	String result = "";
    	if(null == url) {
    		return "";
    	}
    	
    	try {
			result = URLDecoder.decode(url, ENCODE);
		} catch (UnsupportedEncodingException e) {
			e.printStackTrace();
		}
    	return result;
    }
    
    /**
     * URL 转码
     * 
     * @param url
     * @return
     */
    public static String getURLEncoderString(String url) {
    	String result = "";
    	if(url == null) {
    		return "";
    	}
    	
    	try {
			result = URLEncoder.encode(url, ENCODE);
		} catch (UnsupportedEncodingException e) {
			e.printStackTrace();
		}
    	
    	return result;
    }
    
    /**
     * 将map转换为请求参数（&）
     * 
     * @param data
     * @return
     */
    public static String urlencode(Map<String, Object> data) {
    	StringBuilder sb = new StringBuilder();
    	for(Map.Entry i : data.entrySet()) {
    		try {
				sb.append(i.getKey()).append("=").append(URLEncoder.encode(i.getValue() + "", "UTF-8")).append("&");
			} catch (UnsupportedEncodingException e) {
				// TODO Auto-generated catch block
				e.printStackTrace();
			}
    	}
    	return sb.toString();
    }
}
